Current Bioactive Compounds - Volume 11, Issue 3, 2015

Lipophilicity, expressed quantitatively through the LogP, is the most important physicochemical property for pharmacodynamic and pharmacokinetic characterization of the tested compound, as well as the most widely used parameter for quantitative structure-activity relationships (QSAR) descriptions. For this purpose three analytical techniques: the classical Shake Flask, the innovative Vortex-Assisted Liquid-Liquid Micro-Extraction (VALLME), and HPLC method, have been employed for the LogP determination of naturally occurring oxyprenylated secondary metabolites such as boropinic and geraniloxyferulic (GOFA) acid. These techniques have allowed us to correctly determine the LogP value for model molecule (ferulic acid) and from the comparison, by means of statistical techniques, of the obtained results it was possible to determine, not only for the first time, the LogP value of these secondary metabolites with interesting biological activity, but it was also possible to highlight the potential and limitations of the used techniques respect to the presence of interfering and / or degradation products.

Neem (Azadirachta indica) leaves have been widely proposed as a traditional medicine and many bioactive compounds have been isolated and characterized. Taking into account the high variability of the constituents content, which is influenced by many factors such as the environment and the crop production technology, a proper and fast analytical method is important for monitoring the chemical composition of the product. Here, we report, for the first time, the NMR-based metabolic fingerprinting of Neem leaves extracts obtained using two different extraction techniques, namely microwave-assisted and conventional extractions. To optimize the recovery of a large range of metabolites, three extraction times (10, 30 and 60 minutes) and three solvents (methanol, chloroform and acetone) were used. The microwave-assisted extraction gave the highest recovery in the case of methanol and acetone, whereas conventional extraction was the best procedure for chloroform.

The purpose of this study was to determine the effectiveness of the methanol, acetone and chloroform extracts of three Hypericum (Hypericaceae) species (Hypericum pruinatum Boiss., Hypericum olimpicum L. and Hypericum sabrum L.) against standard microorganisms, human pathogens, and methicillin-resistant Staphylococcus aureus strains isolated from clinical samples. Antimicrobial activities were conducted by using disc diffusion and broth microdilution methods. The strains were exposed to different plant extracts at concentrations ranging from 6.25 mg/ml to 0.003 mg/ml. It was determined that the chloroform extract of H. scabrum exhibited significant antimicrobial and anti- MRSA activity at doses ranging 3.125-0.0244 mg/ml against strains. The chloroform extracts of other plants had significant antimicrobial activities, too. Overall, the MRSA strains were more affected from extracts than standard microorganisms. Not only the H. olimpicum chloroform, H. pruinatum acetone, and H. scabrum chloroform extracts were determined as the most effective extracts against Streptococcus mutans strain at concentrations of 0.097 mg/ml, 0.195 mg/ml, and 0.195 mg/ml, respectively, but also they manifested good antifungal activity against Candida albicans at doses of 0.195 mg/ml, 0.195 mg/ml, and 0.0244 mg/ml, respectively. Consequently, it was revealed that Hypericum species, tested in this study, had significant antimicrobial and anti-MRSA activity and they may be a natural source of antimicrobial agents and may be used in the pharmacology industry.

The present work focused on antioxidant and enzyme inhibitory potential of different solvent extracts (ethyl acetate, methanol and water) from Artedia squamata. Cholinesterase, tyrosinase, α-amylase and α-glucosidase inhibitory activities of the extracts were tested by microtitre plate assays. Antioxidant abilities were tested using free radical scavenging (DPPH and ABTS), reducing power (FRAP and CUPRAC), total antioxidant capacity and ferric ion chelating assays. The total phenolic contents of these extracts ranged from 26.24 to 35.16 mg GAEs/g extract. Methanol and water extracts showed higher phenolic content, DPPH and ABTS scavenging activity and reducing power activities, while ethyl acetate extract had highest chelating and inhibition abilities on AChE, α-amylase and α- glucosidase. With regard to tyrosinase inhibitory activity, water extract showed a good inhibitory activity with 11.91 mg KAEs/g. Present study showed that Artedia squamata can be considered as good source of natural agents for food and drug applications.

Natural products, especially foods and extracts from plant origin have been successful in treating various disorders in traditional medicine. Piperine, a versatile bioactive compound is found in almost 2000 varieties of piper species from piper genus. The plants containing piperine, particularly, Piper nigrum (black pepper) and Piper longum (long pepper), are widely used in the traditional as well as alternative therapies for both human and domestic illnesses. Effect of piperine on gastrointestinal system, drug metabolizing enzymes, P-glycoprotein and alteration of bioavailability of other drugs are the major area of research. Particularly, bio-enhancing properties of piperine is of clinical importance, as co-administration with drugs for the treatment of human immunodeficiency virus (HIV) infections, pancreatitis, tuberculosis, hyperlipidemia, bronchial asthma and epileptic disorders, resulted in enhanced bioavailability of these drugs. Also investigations are being carried out to elucidate the underlying mechanism of action for the anti-fertility and anti-cancer effects of piperine. Comprehensive data regarding the in silico, safety, pre-clinical pharmacology, clinical studies of piperine and its derivatives are compiled in this review, to act as a guide for future drug development.

Benzazepine, a seven membered aza-heterocyclic ring fused with aromatic unit, is involved in research aimed to evaluate new products that possess interesting biological activities. The aim of this review is to provide an overview of the diverse and important pharmacological activities of benzazepine moiety. This review highlights importance of benzazepine derivatives as anti-depressant, anti-hypertensive, anti-ischaemic, anorectic, anti-histamine agents, AChE inhibitor, TRPV1 antagonist and also in the treatment of hyponatremia. Recent efforts made to discover various pharmacologically active molecules that contain benzazepine moiety are also reported.

Diterpenes 7-ethoxyrosmanol (1) and carnosol (2) were isolated and identified from the extracts of Hyptis dilatata collected in the Orinoco region, Colombia, used traditionally in this region for the treatment of wound infections of cattle. Their stereostructures were elucidated by 1D and 2D NMR experiments including 1H, 13C, COSY, HSQC, HMBC and NOESY. Although compound 1 has been reported previously, its NMR assignments were revised, completed and corrected. These compounds showed a specific antimicrobial activity against Gram (+) strains. The cytotoxic activity of compounds 1 and 2 was evaluated against a panel of three cancer cell lines (MCF7, HeLa and HT29) using curcumin as positive control. Carnosol (2) showed cytotoxic activity against all three cell lines having a similar response as the positive control with an IC50 approximately of 15-20 μg/mL in each case. On the other hand, 7-ethoxyrosmanol (1) showed lower activity than carnosol, with an IC50 approx. of 20-30 μg/mL for the three cancer cell lines. This is the first report on cytotoxic activity against MCF7, HeLa and HT29 cancer cell lines and the antimicrobial activity of compound 1, and the first report on cytotoxic activity against HeLa of compound 2. In addition, the main volatile components of the essential oil of H. dilatata which displayed quorum sensing inhibitory activity were identified by GC/MS analysis. Finally, these results let us to propose H. dilatata as a potential resource of antimicrobial and cytotoxic compounds.

Daisy is a very important medicinal plant and it is used for the purpose of treating many diseases. So, in this study we aimed to determine the antioxidant capacity of different parts of daisy, collected from Tokat-Turkey, with different antioxidant tests such as free radical scavenging activity, scavenging of superoxide anion radical activity. DPPH free radical scavenging activity and superoxide anion radical scavenging activities were higher than

Pleurotus porrigens and Schizophyllum commune contain high amounts of dietary antioxidants such as flavonoids and phenolic acids. Identification of major antioxidative components of selected fractions of P. porrigens and S. commune was determined by high performance liquid chromatography - ion trap tandem mass spectrometry (HPLC-IT/MS). In addition, 2,2-diphenyl-1- picrylhydrazyl (DPPH) radical scavenging ability of the fractions was evaluated. The crude water extracts were subjected to fractionation by means of liquid-liquid partitioning. n-Butanol fraction (P. porrigens) and formic acid residue fraction (S. commune) showed high DPPH radical scavenging activity. Based on HPLC-IT/MS analysis, two flavones glucosides, namely luteolin-7-O-β-glucoside and apigenin-7-O-